Method and apparatus for bending fan spider arms

ABSTRACT

The invention pertains to the method and apparatus for twisting or bending the arms formed upon fan spiders, particularly of the type used to draw air through the cooling radiators of internal combustion engines. Such fans include a fan spider which defines the fan hub, and a plurality of radially extending arms project from the hub. Twisting of the arms to provide the desired pitch to the fan blades is achieved by firmly clamping the spider hub portion upon opposite sides while simultaneously, individually, clamping each arm outer region. Thereupon each arm outer region is simultaneously pivoted about an axis substantially perpendicularly disposed to the axis of the spider hub to impart the desired pitch to the spider arm. Clamping of the arms is accomplished by relatively movable components utilizing uniquely related rotatable portions whereby the two parts of the clamp which are to be rotated are coaxially aligned when clamping and bending.

United States Patent [151 3,641,800

Wickham Feb. 15, 1972 [54] METHOD AND APPARATUS FOR Primary ExaminerCharles W. Lanham BENDING FAN SPIDER ARMS Sampatacos.. 272/299 Esken et al. ..72/299 Assistant Examiner-Michael J. Keenan Attorney-Beaman & Beaman [57] ABSTRACT The invention pertains to the method and apparatus for twisting or bending the arms formed upon fan spiders, particularly of the type used to draw air through the cooling radiators of internal combustion engines. Such fans include a fan spider which defines the fan hub, and a plurality of radially extending arms project from the hub. Twisting of the arms to provide the desired pitch to the fan blades is achieved by firmly clamping the spider hub portion upon opposite sides while simultaneously, individually, clamping each arm outer region. Thereu-.

pon each arm outer region is simultaneously pivoted about an axis substantially perpendicularly disposed to the axis of the spider hub to impart the desired pitch to the spider arm. Clamping of the arms is accomplished by relatively movable components utilizing uniquely related rotatable portions whereby the two parts of the clamp which are to be rotated are coaxially aligned when clamping and bending.

4 Claims, 12 Drawing Figures PATENTEDFEB 15 m2 SHEEI 1 [IF 7 INV'ENTOR ROBERT G. WICKHAM ATTORNEYS PATENTEDFEB 15 m2 3.641.800

' sum 3 OF 7 I INVENTOR OBERT c. WICKHAM ATTORNEYS PATENTEDFEB 1 5 I972 3.641. ,80O

sum 6 or 7 INVENTOR ATTORNEYS PATENTEU FEB 15 m2 SHEET 7 BF 7 FIG. 10

INVENTOR ROBERT G. WICKHAM ATTOR NEYS /i Z /6 M METHOD AND APPARATUS FOR BENDING FAN SPIDER ARMS BACKGROUND OF THE INVENTION The invention pertains to method and apparatus for forming sheet metal articles by twisting a portion of the article about an axis while other portions of the article are rigidly clamped whereby a permanent deformation by twisting is produced.

In the manufacture of fan spiders, such as the type widely used in the internal combustion engine field for forcing air through cooling radiators, it is the common practice to form the spider of a sheet metal construction wherein the spider includes a central hub portion having a plurality of arms extending therefrom. Fan blades are attached to the spider arms, usually by rivets, and the pitch of the fan blade may be achieved by either twisting the fan blade adjacent the arm, or twisting the spider arm and utilizing a generally planar fan blade. In that the fan spider is formed of a heavier gauge material than the fan blade, there are advantages to achieving the blade pitch by twisting the spider arm relative to the spider hub due to the increased resistance to vibration and noise problems, and the strength achieved.

In the usual manufacture of fan spiders, the spider is formed of sheet material and is of a planar configuration prior to bending of the arms to impart the desired pitch" thereto. Previously, the bending or twisting of fan spider arms was accomplished manually, or in press-type machines wherein control of the degree and location of twisting is difiicult to maintain. The circumferential spacing of the arms about the hub portion may vary slightly, and thus it is of utmost importance that when forming the fan spider arms the unformed blank be properly located within the twisting apparatus, and that each arm be formed in accordance with the desired specifications. Previous apparatus for twisting fan spider arms has not had the degree of flexibility desired, and the twisting of such arms has, prior to the development of the present invention, been an expensive and troublesome operation.

SUMMARY OF THE INVENTION It is the purpose of the invention to provide a method and apparatus for bending or twisting the arms of a fan spider so as to produce the desired pitch" wherein the bending of the arms is automatically accomplished with a high degree of accuracy, and may be consistently performed.

In the practice of the invention the fan spider hub portion is rigidly clamped between clamping surfaces wherein the bending of the arms does not impart undesirable forces or deflection upon the hub. Additionally, the spider arms are also clamped at those outer regions thereof to which the fan blades will be attached. Thus, the outer portion of the arms will be maintained in a planar configuration even after twisting or bending of the arm portion adjacent the hub has occurred. The configuration of the apparatus of the invention maintains those portions of the fan spider which serve as reference or attachment portions planar to permit accurate assembly and location on the associated apparatus. Likewise, by precisely locating the clamping surfaces of the apparatus with respect to the fan spider, the location at which bending occurs in the arms may be very closely regulated and maintained.

In the forming of the bend within the spider arms, the central region of the spider is rigidly clamped between opposed flat clamping surfaces. Individual clamping members also engage the opposite sides of each spider arm at its outer fan attachment portion. That portion of the spider arm intermediate the outer portion and the hub is not clamped or otherwise restricted, and this neck" portion of the arm is that location wherein the bending occurs. The lower" clamping surfaces of the apparatus of the invention are mounted upon a fixed table of the apparatus. The upper clamping surfaces of the apparatus are mounted upon a head which is movable toward and away from the table, and the opposed clamping surfaces for the fan spider and arms are defined upon these two relatively movable components. In that twisting of the arms occurs about an axis substantially perpendicular to the axis of rotation of the completed fan, it will be appreciated that bending of the arms by a rotation thereof about such an axis becomes a problem when clamping structure of the above type. In order to permit the rotation of the arms necessary for bending, the clamping surfaces engaging the arm outer portions are mounted upon cylindrical bearing components, each of substantially which, when located in the clamping position, become coaxial and define a complete 360 cylinder capable of being rotated about the desired axis. Thus, before bending or twisting of the arms occurs, the arm engaging clamping surfaces defined on the table and the head must become coaxial.

As it is most important that the axis of rotation of the arms be accurately located with respect to the arms, and the other fan spider components, and as the degree of bending of each arm must be closely regulated, the clamping surfaces engaging the arms are mounted upon adjustable means which permit adjustment in a circumferential direction with respect to the hub portion clamping members.

Rotation of the spider arm clamps is accomplished through a linkage system wherein all of the spider arms may be simultaneously bent to the degree desired. In the apparatus disclosed, the rotation of the clamping members associated with the arms is imposed upon one of the clamping surfaces, i.e., the lower" clamping component surface, and the upper clamping member, by utilizing cylindrical bearing means, is able to follow and rotate with the lower clamping member during the arm bending. Thus, by forming one portion of the clamp as an idler the apparatus required to perform the method of the invention is simplified without sacrificing the degree of engagement desired between the clamp and the fan spider arm.

A further object of the invention is to provide a method and apparatus for bending the arms of fan spiders wherein the arms are individually and simultaneously bent to the desired degree, and yet the location of the clamping and bending apparatus with respect to the die may be simultaneously regulated at each arm clamping location.

The construction of the apparatus in accord with the invention permits the fan spider to be quickly and easily loaded into the apparatus, and properly positioned therein. Likewise, the construction of the bending apparatus permits the formed spider to be readily removed therefrom. The apparatus of the invention lends itself to use with automatic loading and unloading apparatus and setup time and maintenance requirements are minimized due to the unique relationship of parts and components.

BRIEF DESCRIPTION OF THE DRAWINGS The aforementioned advantages and objects of the invention will be apparent from the following written description and the accompanying drawings wherein:

FIG. 1 is an elevational view of apparatus constructed in accord with the invention, partially sectioned for purpose of illustration,

FIG. 2 is a plan view through the machine of the invention illustrating the appearance of lower components with the upper clamping members removed therefrom when taken along Section 1 1l1 of FIG. 1,

FIG. 3 is a plan, sectional view taken through the lower regions of the apparatus illustrating the link structure and lower head as taken along Section 1 11-111 of FIG. 1,

FIG. 4 is a plan view of the apparatus in accord with the invention as taken along Section IVIV of FIG. 1 illustrating the means for adjusting the stop apparatus for the lower head,

FIG. 5 is an enlarged, detail, elevational view, partly in section, illustrating the outer configuration of one of the armbending locations, partially in section, as taken along Section V-V of FIG. 1, and illustrating the normal position of the link in full lines, and the linkage position at the completion of bending in dotted lines,

min-n m" FIG. 6 is an enlarged, detail, elevational, sectional view illustrating one of the arm-bending locations during clamping, and prior to bending, as taken along Section VI-VI of FIG. 5,

FIG. 7 is an enlarged elevational view of the upper clamping portion of an arm-bending location prior to mating with the lower clamping portion,

FIG. 8 is an enlarged, elevational, sectional view of the structure which permits rotation of the arm clamping pads as taken along Section VIIIVIII of FIG. 6,

FIG. 9 is an enlarged, detail, plan view of support structure for one of the arm-bending locations, partially sectioned, as taken along Section lX-IX of FIG. 6,

FIG. 10 is an enlarged, detail, elevational, sectional view taken through the adjusting block of an arm bending location along Section XX of FIG. 9,

FIG. 11 is a detail perspective view of a fan spider arm before being bent, and

FIG. 12 is a view similar to FIG. 11 showing the fan spider arm after being bent.

DESCRIPTION OF THE PREFERRED EMBODIMENT The configuration of a fan spider of the type with which the apparatus of the invention is employed will be understood from FIGS. 2, II and 12. In FIG. 2, four of the arms of a seven-armed fan spider I are illustrated. The spider is normally formed of a sheet steel material of approximately five thirty-seconds of an inch thickness and includes a planar hub portion 12 from which the arm portions 14 radially extend. The outer portion of the arms constitute attachment portions I6, and have a plurality of holes defined therein for receiving rivets whereby the fan blades may be attached thereto. That portion of the arms designated by the numeral 18 constitutes the neck of the arm, and is located adjacent the hub portion, and it is within this portion of the arm that the bending occurs wherein the arm portions 14 are twisted or bent to define a pitch" with respect to the plane of the hub portion 12.

The basic relationship of the components of apparatus capable of performing the steps of the method of the invention is illustrated in FIG. 1. Basically, the apparatus includes a frame consisting of a lower box or frame 20 in which the plate 22 is located. Four columns 24 extend from the plate 22 in a vertical manner, and at their upper regions support the frame box 26 of the frame in which the plate 28 is mounted. The columns 24 are partially threaded and are surrounded by spacer sleeves 30 at their lower region which serve as a support for the table 32 resting upon the sleeves and through which the columns pass. Nut members threaded upon the columns 24 maintain the table fixed with respect to the columns and the other previously described frame components.

The table 32 serves as a support for the plate 34, and the lower central clamping pad structure is mounted upon the block 36 bolted by bolts 38 to the central region of the plate. The block 36 includes a recessed clamping pad or plate 40 bolted thereto, FIG. 6, and the upper surface of the pad 40 is in substantial alignment with the upper edge of the block which is radiused at 42, FIG. 6. The configuration of the block 36 and the pad 40, is substantially cylindrical, wherein the block defines a periphery 44, FIG. 6, and the diameter of the block is only slightly larger than the diameter of the fan spider hub portion 12.

A head plate 46 is mounted above the table 32 upon bearin g guides 48 slidable on the columns 24 wherein the head 46 may be moved toward and away from the table. A hydraulic ram 50 mounted upon the frame plate 28 includes a piston 52 connected to the head 46 for movement of the head in a vertical manner.

As will be apparent from FIG. 6, the head 46 includes a plate 54 bolted thereto having a central region which serves as the support for the upper spider hub portion clamping pad 56, bolted to the plate at 58. The pad 56 is in an opposed relationship to the lower clamping pad 40 whereby the spider hub 12 will be firmly clamped between the pads 40 and 56 upon the head 46 being moved toward the table 32 its maximum extent as disclosed in FIG. 6.

Each of the arms 14 of the fan spider are independently associated with clamping pad means for holding and bending the associated arm. Thus, with a seven arm spider, as illustrated, seven arm-bending locations will be disposed about the periphery of the hub clamping block 36 and pad 56. As the arm-bending stations are identical in construction a single station will be described in detail with particular reference to FIGS. 5 through 8.

The plate 34 is formed with a circular groove 60 in which a circular adjusting ring 62 is slidably received. The ring 62 includes an arm 64, FIG. 2, radially extending therefrom which associates with a screw-type adjustment 66 mounted upon the table 32, and an indicia gauge 68 associates with a pointer on the arm 64 to indicate the relative position thereof.

The ring 62 is provided with a rectangular opening 70 at each arm-bending location and a Tee-shaped block 72 includes a leg 74 which is received within each opening 70. The radial dimension of the leg 74 is less than the corresponding radial dimension of the opening, as will be apparent in FIG. 6, and the head 76 of the block 72 fits into a rectangular recess 78 defined in a guide block 80 mounted upon the plate 34. The recess 78, FIG. 9, is of a larger tangential dimension than the head 76 of the Tee block and adjustment screws 82 threaded into the guide block 80 engage the ends of the Tee block 72 for adjustment purposes as will be later described.

The guide block 80 is guided for movement in a direction somewhat tangential with respect to the axis of the clamping pads and the general vertical axis of the apparatus. The guiding of the block 80 is achieved by a dovetail guide 84 bolted to the plate 34 which associates with a dovetail portion on the block 80, FIG. 6, and an opposed combination dovetail guide and clamp 86 which bears on block 80 is also connected to the plate 34 by means of screws 88. It will therefore be appreciated that by loosening the screws 88, and adjusting the adjustment screws 82, FIG. 9, that the guide block 80 can be moved in its tangential direction relative to the ring 62 intermediate the guides 84 and 86 a distance limited by the clearance provided between the Tee block head 76 and the recess 78. When so adjusting the guide block 80 one of the screws 82 must be backed off from the Tee block head 76 and the other screw 82 is threaded toward the Tee block which will produce a shifting of the guide block with respect to the adjustment ring 62.

It will also be appreciated that all of the guide blocks 80 at each arm-bending location can be simultaneously adjusted by loosening the screws 88 at each location and adjusting the ring 62 by means of the adjustment 66, FIG. 2. In this manner an angular shifting of all of the arm-bending locations about the apparatus axis can be simultaneously accomplished, and yet the bending locations can also be individually adjusted with respect to the ring 62.

A block 90 is mounted upon each of the guide blocks 80 by bolts 92 and each block 90 is provided with a cylindrical bore 94 which receives a cylindrical sleeve bearing 96, FIG. 6. The configuration of the block 90, and the sleeve bearing 96, is such that the complete circular configuration of the bore 94 exits only at the outer portion of the block and the block is recessed at 98 such that the inner portion of the block is capable of receiving the upper arm clamping pad components.

A clamping pad 100 is rotatably received within the bearing 96, and this pad is of a circular configuration at its outer regions wherein it is received within the complete circular configuration of the bearing, and it is of a semicircular configuration in the inner region defining the flat clamp pad surface 102, FIGS. 6 and 8. The clamp pad is radiused at 104 adjacent the location where the arm bending occurs to prevent tearing or undue stressing of the fan spider arm neck at this location.

Rotation of the clamping pad 100 is produced by a crank arm 106 affixed to the outer end of the clamping pad by bolts 108 and a key 110. The crank arm includes an offset portion,

IDIOT; 4

FIG. 5, eccentrically disposed with respect to the axis of rotation of the clamping pad provided with a pivot shaft and hearing structure 112 which associates with the operating linkage, as is later described.

The structure for holding the upper arm clamping pad is similar in many respects to that employed with the lower clamping pad, and with reference to FIG. 6, apparatus identical to that previously described is indicated by primed reference numerals. The upper arm clamping pad apparatus can be simultaneously adjusted at all ann locations by means of the adjusting ring 62', and an adjustment arm, now shown, similar to that of arm 64 is utilized with the mounted upon the head plate 54.

A block 114 is mounted upon the guide block 80 by means of screws 116, FIG. 6, and it will be appreciated that the verti cal dimension of the block 114 is greater at its inner regions than at its outer region wherein clearance is provided for the maximum vertical dimension of the block 90. A semicylindrical concave surface 118 is defined on the lower portion of the block 114, FIGS. 6 through 8, and the block is provided with Tee shaped grooves 120 of a cylindrical configuration for receiving the guide bearings 122 affixed to the upper clamping pad 124. The upper clamping pad 124 is of a generally semicylindrical configuration and includes a lower flat surface 126 for directly engaging the fan spider arm outer portion in opposed relation to the lower clamping pad surface 102.

A recess 128 is defined in the block 114 of an arcuate configuration, FIG. 8, and receives a compression spring 130 which bears against a threaded stud 132 defined in the clamping pad 124 and an anchoring screw 134 defined in the block 114. The tendency of the spring 130 is to rotate the clamping pad 124 in a counterclockwise direction, FIG. 8, until the stud 132 engages the shoulder 136 of the block 114; at this time the pad surface 126 will be in the horizontal orientation shown in full lines in FIG. 8. However, the guide bearings 122 and the spring, permit the clamping pad 124 to be rotated in the clockwise direction as indicated in dotted lines of FIG. 8.

The bending of the fan spider arms 14 is accomplished by a rotation of the clamping pads 100 and 124 actuated through a plurality of linkages connected to the lower clamping pads 100. This structure includes a hydraulic ram 138 affixed to the underside of the table 32 having a piston 140 attached to a lower head 142. The lower head 142 is slidably mounted upon columns 146 interposed between the frame baseplate 22 and the table 32. Guide bearings defined upon the head 142 permit accurate movement of the head upon the threaded columns 146, and nonthreaded columns 148 also serve as guides, as well as means for supporting the central region of the table 32.

A Tee groove 150 of a circular configuration is defined in the head 142 adjacent its periphery, FIG. 3, and shaped pivot blocks 152 are adapted to be received within the groove for selective orientation therein. The pivot blocks 152 are adjusted in the head to be located below each arm-bending location and a linkage, as shown in FIG. 5, is interposed between each pivot block 152 and each lower clamping pad crank pivot 112. These linkages, generally designated at 154, FIG. 5, include a lower head 156 pivotally connected to a pivot block 152 by a pivot pin 158, a threaded shaft 160 extends therefrom, and is threaded into the tubular sleeve 162, Locknuts 164 permit the distance between the sleeve and the head 156 to be adjusted and fixed. A rod 166 having an enlarged head 168 is received within the sleeve 162, and a cap 170 is threaded upon the sleeve to maintain the rod head therein. A compression spring 172 surrounds the rod 166 and bears upon the cap 170 while the upper end of the spring engages nut 174 associated with the rod pivot end 176 which is journaled to the crank arm pivot 112.

The vertical dimension of the sleeve 162, and the recess therein, is substantially greater than the vertical dimension of the rod head 168, and thus a relative telescoping or lost motion" exists between the sleeve and the rod 166 which is under the biasing influence of the spring 172.

In that the amount of bend or twist that is to be imposed upon the fan spider arms must be very accurately regulated, stop apparatus is mounted upon the frame to accurately limit the movement of the head 142 in the direction of movement which causes fan spider arm bending. This stop structure includes a gear 178 rotatably mounted upon a shaft 180 journaled in a base member 182 affixed to the plate 22, FIG. 1. A worm wheel 184 is attached to the lower end of the shaft 180 and meshes with a worm screw 186, FIG. 4, connected to a hand-operable wheel 188 by means of an elongated shaft. A stop nut 190 is mounted upon the threaded portion 192 of each of the guide columns 146, and the nuts each include a gear portion 194 and a wear plate 196 disposed toward the head 142. In that the gear 178 simultaneously meshes with all of the stop nuts 190, rotation of the gear will simultaneously adjust each of the three stop nuts upwardly or downwardly, and as the bearing sleeves of the head 142 will engage the nut wear plates 196 as the head moves downwardly during its power stroke, the positioning of the nuts 190 will accurately determine the length of movement of the ram piston 140, and thus the degree of rotation of the fan spider arms to produce the desired bending thereof.

In operation, the rams 50 and 138 will initially be in their retracted positions wherein the head 46 will be raised from the table 32, and the head 142 will also be in its uppermost position. In FIG. 1 the head 46 is shown in its lowermost clamping position, while the head 142 is shown in its uppermost, position. With both of the rams raised," access is provided between the table 32 and the head 46 wherein the fan spider 10 may be located upon the clamping pad 40 and the pads as shown in FIG. 2. Proper location of the spider on the clamping pads can be accomplished by the provision of upstanding lugs 198, FIG. 6, extending from the clamping pad block 36 to engage the neck portion 18 of the fan spider.

Upon the fan spider being properly located on the lower clamping pad 40, and pads 100, the ram 50 is energized to lower the head 46, and the upper clamping structure into engagement with the fan spider as shown in FIGS. 1 and 6. Lowering of the head 46 causes the central upper clamping pad 56 to firmly press upon the hub portion 12 of the fan spider as it is sandwiched" between the clamping pads 40 and 56. Likewise, each of the attachment portions 16 will be firmly clamped between the lower clamping pad surface 102 and the upper clamping pad surface 126. In that the springs bias the upper clamping pads 124 in a direction which causes the upper pad surface 126 to be horizontal, this orientation exists when the head 46 is lowered into engagement with the fan spider.

The blocks 114 each include a pair of spaced guide pins 200, FIG. 7, downwardly extending from the block, and these guide pins are adapted to be received within guide holes 202, FIG. 2, defined within the lower blocks 90 upon each side of the bore 94. The presence of the guide pins 200 establishes a positive alignment between the upper and lower blocks 90 and 114 upon the head 46 being lowered into engaging relationship with the fan spider.

The vertical relationship of the blocks 90 and 114 is predetermined such that upon the fan spider arms being firmly clamped between the clamping pads 100 and 124, the axis of the bore 94 and the clamping pad 100 will coincide with the axis of the upper clamping pad 124. Thus, as is apparent in FIG. 6, the clamping pads 100 and 124, in efiect, constitute a single member rotatable about a common axis, even though the clamping pads are mounted upon separable supporting elements.

After the fan spider is firmly clamped between the head 46 and the table 32, the ram 138 is energized to lower the head 142 until the sleeves thereof engage the wear plates of the stop nuts 190. Lowering of the head 142 causes the cap of the sleeve 162 to engage the link rod head 168 and thereby exert a clockwise rotational force on the crank arms 106, FIG. 5. As the head 142 is lowered the links 154 are lowered, and the crank arms are rotated to the dotted line position shown in FIG. 5. Rotation of the crank arm 106, of course, causes the cylindrical clamping pad 100 to rotate about its axis. This rotation also imparts a rotation to the upper clamping pad 124, and each pair of upper and lower opposed clamping pads 100 and 124 will be rotated about its common axis in a manner as will be apparent from the dotted line position shown in FIG. 8. This rotation of the pads 100 and 124 causes the fan spider arm attachment portion disposed between the clamping pads to be twisted about the axis of the clamping pads, and the twisting within the spider arm occurs in the neck portion 18 of the arm that is not in engagement with clamping surfaces, as apparent in FIG. 6. In that all of the links 154 are attached to the head 142, it will be appreciated that simultaneous bending of the seven fan spider arms occurs.

The degree of rotation of the crank arms 106 and arm-engaging clamping pads is adjusted by shaft 160 and nuts 190 to produce the desired pitch in the fan spider arms. Upon the desired bending of the arms being completed the ran 50 is energized to raise the head 46, while the ram 138 is still in its extended condition. Once the head 46 has sufficiently lifted to disengage the upper clamping pads 124 from the fan spider arms the ram 138 is then energized to raise the head 142 and return the lower clamping pads 100 to their initial horizontal orientation. The presence of the lost motion movement in the links 154 assures that a reverse bending of the arms will not occur during the retracting of the rams, yet it is preferred that the upper ram 50 be raised prior to the raising of the lower ram.

The biasing force imposed by the spring 172 to return the clamping pads 100 to the horizontal position facilitates removal of the formed fan spider from the apparatus, and the operation is now ready for its next cycle.

The resultant bending that has occurred in the neck portion of the fan spider arms will be apparent from a comparison of FIGS. 11 and 12.

[n that the apparatus of the invention firmly clamps the hub portion 12 of the fan spider, and the outer portions 16 of the arms, these clamped portions will retain their original planar configuration during bending, and undesired deformation of the fan spider is prevented during bending of the arms by predetermining the spacing between the central clamping structure, and the arm-clamping structure, the location of the bending, and the configuration of the bend occurring in the arm neck portion 18 can be accurately regulated. Additionally, the adjustable mounting of the arm-clamping pads permits the clamping pads to be very accurately related to the spider arms, and if it is desired that the axis of arm bending be shifted with respect to a particular arm, this procedure can be readily accomplished. In the manufacture of fan spiders and fans the spacing of the arms about the hub portion is often such that the arms are not equally spaced, but are offset for purposes of vibration dampening, noise reduction, etc., and thus the apparatus of the invention may be readily adjusted to accommodate a wide variety of fan spider blanks.

If it is desired to bend the arms of a fan spider which has a different number of arms than that of the disclosed embodiment, the table 32 is replaced with another table having the appropriate number of bending stations thereon, and, likewise, a different set of upper bending components are affixed to head 46 which correspond to the bending structure on the table 32. The provision of Tee-groove 150 permits the head 142 to be connected to any number of bending locations that may be mounted on table 32.

I claim:

1. Apparatus for bending fan spider arms defined on a fan spider blank having a central hub portion and a plurality of radial arms extending therefrom comprising, in combination, a frame, fan spider hub portion clamping means defined on said frame having a hub portion axis, a plurality of fan spider arm clamping means defined on said frame disposed about said hub portion clamping means, bearing means supporting each of said arm-clamping means for individual rotation about axes radially disposed with respect to said hub portion axis, in

dividual adjustment means mounting said arm-clamping means upon said frame for individual angular adjustment of said arm-clamping means bearing means axes about said hub portion axis whereby the angular spacing between adjacent arm-clamping means may be varied, common adjustment means supporting said individual adjustment means whereby said arm clamping means may be simultaneously adjusted about said hub portion axis, and means for rotating said fan spider arm-clamping means about their individual axes of rotation.

2. Apparatus for bending the arms of fan spiders defined on a fan spider blank having a central hub portion and arms wherein the arms radially extend from the hub portion and include an outer blade attachment portion and a neck portion adjacent said hub portion comprising, in combination, a frame, a table fixed on said frame having first and second oppositely disposed sides, a first head movably mounted on said frame, first power means mounted on said frame for selectively moving said head toward and away from said table, a first flat fan spider hub portion clamping pad defined on said table having an axis and a periphery, a second fiat fan spider hub portion clamping pad defined on said head in opposed relation to said first pad, a plurality of first arm outer portion clamping pads mounted on said table disposed about the periphery of said first hub portion clamping pad, a plurality of second arm outer portion clamping pads mounted on said head adjacent said second hub portion clamping pad and each in opposed relation to a first arm portion pad, rotary bearing means defined on said table and said head having axes radially disposed to said hub portion clamping pad axis and supporting said first and second arm outer portion clamping pads, respectively, the axes of said bearing means of opposed arm outer portion clamp pads being coaxial upon said opposed pads simultaneously clamping a fan spider arm outer portion therebetween, second power means mounted on said frame connected to said first arm outer portion clamping pads for rotating said pads about the axis of the associated bearing means to bend the clamped arms at their neck portions, biasing means connected to said second arm outer portion clamping pads biasing said second pads in a direction of rotation opposite to that produced by said second power means during arm bending for returning said second clamping pads to the initial clamping position upon movement of said first head away from said table, a second head movably mounted on said frame disposed on the opposite side of said table with respect to said first head, said second power means being connected to said second head for movement thereof toward and away from said table, a crank arm connected to each of said first arm outer portion clamping pads for the rotation thereof about its axis, and a link connecting each of said crank arms to said second head.

3. Apparatus for bending the arms of fan spiders as in claim 2, including stop means defined on said frame disposed within the path of movement of said second head when moving in a direction to rotate said arm outer portion clamping pads, and adjustment means associated with said stop means for adjusting the position thereof and thereby regulating the degree of bending of the fan spider arms.

4. Apparatus for bending the arms of fan spiders defined on a fan spider blank having a central hub portion and arms wherein the arms radially extend from the hub portion and include an outer blade attachment portion and a neck portion adjacent said hub portion comprising, in combination, a frame, a table fixed on said frame having first and second oppositely disposed sides, a first head movably mounted on said frame, first power means mounted on said frame for selectively moving said head toward and away from said table, a first flat fan spider hub portion clamping pad defined on said table having an axis and a periphery a second flat fan spider hub portion clamping pad defined on said head in opposed relation to said first pad, a plurality of first arm outer portion clamping pads mounted on said table disposed about the periphery of said first hub portion clamping pad, a plurality of second arm outer portion clamping pads mounted on said head adjacent said second hub portion clamping pad and each in opposed relation to a first arm portion pad, rotary bearing means defined on said table and said head having axes radially disposed to said hub portion clamping pad axis and supporting said first and second arm outer portion clamping pads, respectively, the axes of said bearing means of opposed arm outer portion clamp pads being coaxial upon said opposed pads simultaneously clamping a fan spider arm outer portion therebetween, second power means mounted on said frame connected to said arm outer portion clamping pads for rotating said pads about the axis of the associated bearing means to bend the clamped arms at their neck portions, and first and second arm common outer portion clamp pad adjustment means defined on said table and first head, respectively, said first and second arm outer portion clamp pads being mounted on said first and second common adjustment means, respectively, for adjustment in a direction about the periphery of said fan spider hub portion clamping pads and individual outer portion clamp pad adjustment means interposed between each of said outer portion clamp pads and its associated common adjustment means for adjustment of said outer portion clamp pads relative to its common adjustment means. 

1. Apparatus for bending fan spider arms defined on a fan spider blank having a central hub portion and a plurality of radial arms extending therefrom comprising, in combination, a frame, fan spider hub portion clamping means defined on said frame having a hub portion axis, a plurality of fan spider arm clamping means defined on said frame disposed about said hub portion clamping means, bearing means supporting each of said arm-clamping means for individual rotation about axes radially disposed with respect to said hub portion axis, individual adjustment means mounting said arm-clamping means upon said frame for individual angular adjustment of said arm-clamping means bearing means axes about said hub portion axis whereby the angular spacing between adjacent arm-clamping means may be varied, common adjustment means supporting said individual adjustment means whereby said arm clamping means may be simultaneously adjusted about said hub portion axis, and means for rotating said fan spider arm-clamping means about their individual axes of rotation.
 2. Apparatus for bending the arms of fan spiders defined on a fan spider blank having a central hub portion and arms wherein the arms radially extend from the hub portion and include an outer blade attachment portion and a neck portion adjacent said hub portion comprising, in combination, a frame, a table fixed on said frame having first and second oppositely disposed sides, a first head movably mounted on said frame, first power means mounted on said frame for selectively moving said head toward and away from said table, a first flat fan spider hub portion clamping pad defined on said table having an axis and a periphery, a second flat fan spider hub portion clamping pad defined on said head in opposed relation to said first pad, a plurality of first arm outer portion clamping pads mounted on said table disposed about the periphery of said First hub portion clamping pad, a plurality of second arm outer portion clamping pads mounted on said head adjacent said second hub portion clamping pad and each in opposed relation to a first arm portion pad, rotary bearing means defined on said table and said head having axes radially disposed to said hub portion clamping pad axis and supporting said first and second arm outer portion clamping pads, respectively, the axes of said bearing means of opposed arm outer portion clamp pads being coaxial upon said opposed pads simultaneously clamping a fan spider arm outer portion therebetween, second power means mounted on said frame connected to said first arm outer portion clamping pads for rotating said pads about the axis of the associated bearing means to bend the clamped arms at their neck portions, biasing means connected to said second arm outer portion clamping pads biasing said second pads in a direction of rotation opposite to that produced by said second power means during arm bending for returning said second clamping pads to the initial clamping position upon movement of said first head away from said table, a second head movably mounted on said frame disposed on the opposite side of said table with respect to said first head, said second power means being connected to said second head for movement thereof toward and away from said table, a crank arm connected to each of said first arm outer portion clamping pads for the rotation thereof about its axis, and a link connecting each of said crank arms to said second head.
 3. Apparatus for bending the arms of fan spiders as in claim 2, including stop means defined on said frame disposed within the path of movement of said second head when moving in a direction to rotate said arm outer portion clamping pads, and adjustment means associated with said stop means for adjusting the position thereof and thereby regulating the degree of bending of the fan spider arms.
 4. Apparatus for bending the arms of fan spiders defined on a fan spider blank having a central hub portion and arms wherein the arms radially extend from the hub portion and include an outer blade attachment portion and a neck portion adjacent said hub portion comprising, in combination, a frame, a table fixed on said frame having first and second oppositely disposed sides, a first head movably mounted on said frame, first power means mounted on said frame for selectively moving said head toward and away from said table, a first flat fan spider hub portion clamping pad defined on said table having an axis and a periphery a second flat fan spider hub portion clamping pad defined on said head in opposed relation to said first pad, a plurality of first arm outer portion clamping pads mounted on said table disposed about the periphery of said first hub portion clamping pad, a plurality of second arm outer portion clamping pads mounted on said head adjacent said second hub portion clamping pad and each in opposed relation to a first arm portion pad, rotary bearing means defined on said table and said head having axes radially disposed to said hub portion clamping pad axis and supporting said first and second arm outer portion clamping pads, respectively, the axes of said bearing means of opposed arm outer portion clamp pads being coaxial upon said opposed pads simultaneously clamping a fan spider arm outer portion therebetween, second power means mounted on said frame connected to said arm outer portion clamping pads for rotating said pads about the axis of the associated bearing means to bend the clamped arms at their neck portions, and first and second arm common outer portion clamp pad adjustment means defined on said table and first head, respectively, said first and second arm outer portion clamp pads being mounted on said first and second common adjustment means, respectively, for adjustment in a direction about the periphery of said fan spider hub portion clamping pads and individual outer portion clamp pad adjustment means interposed between each of saiD outer portion clamp pads and its associated common adjustment means for adjustment of said outer portion clamp pads relative to its common adjustment means. 